US2574586A - Tool-supporting device - Google Patents

Description

Nov. 13, 1951 E. c. OLIVER 2,574,586

TOOL-SUPPORTING DEVICE Filed Oct. 11, 1946 Sheets-Sheet l mmyron fda C. U/A/er Mam Nov. 13, 1951 E. c. OLIVER 2,574,535

TOOL-SUPPORTJ ING DEVICE Filed Oct. 11, 1946 3 Sheets-Sheet 2 IN V EN TOR.

W ATTORNEY Nov. 13, 1951 E0. OLIVER 2,574,586

TOOL-SUPPORTING DEVICE Filed Oct. 11, 1946 3 Sheets-Sheet 3 INVENTOR. LL- P 50% C O/z'ver ATTORNEY Patented Nov. 13, 1 951 2,574,586 TOOL-SUPPORTING DEVICE Edd C. Oliver, Adrian, Mich.; Genevieve R.

Oliver, executrix of said Edd C. Oliver, deceased, assignor to Genevieve R. Oliver, Adrian,

Mich.

Application October 11, 1946, Serial No. 702,770

1 Claim.

and more especially to an arrangement or fixture for supporting a form tool blank or tool bit during contouring, grinding or sharpening operations.

In the art of forming or grinding form tool bits This invention relates to tool holding devices for machine operations difiiculties have been exon different portions of a tool bit, for example,

it may be desirable to impart a different clearance angle to each of the leading, front or trailing edge portions of the tool bit.

The present invention embraces the provision of means for supporting a form tool bit during contouring or grinding operations wherein various clearance angles may be formed on different portions of the tool bit.

The invention comprehends the provision of a tool supporting means particularly adaptable for use with a grinding machine for forming cutting edge portions upon form tool bits, the arrangement having provision of means for adj ustably mounting a tool to obtain various degrees of clearance for the cutting portion of the tool bit.

Another object is the provision of a means of imparting a predetermined configuration to tool bits utilizing a template or pattern whereby the tool bit may be formed to predetermined configuration. I

Still another object of the invention is the provision of a tool bit mounting fixture having a tool bit supporting means arranged for universal adjustment whereby the tool bit may be brought into engagement with a grinding or abrasive medium in a manner to impart compound angles of clearance to the tool bit.

Still a further object resides in the provision of a tool bit supporting fixture equipped with a template of larger size than the tool bit to be formed from the configuration of the template whereby a high degree of accuracy for the tool bit form is assured.

Further objects and advantages are within the scope of the invention such as relate to the arrangement, operation andfunction of the related elements of the structure to various details of construction and to combination of parts, elements per se, and to economies of manufacture and numerous other features as will be apparent from a consideration of the specification and drawing of a form of the invention, which may be preferred, in which:

Figure 1 is an elevational view of a portion of a grinding machine with which the arrangement of my invention has particular utility;

Figure 2 is a side elevational view showing a form of tool holder of my invention;

Figure 3 is a front elevational view of the arrangement shown in Figure 2;

Figure 4 is a vertical sectional view through the tool holder; v

Figure 5 is a fragmentary elevational view illustrating a compound setting for a tool bit supporting means;

Figure 6 is a front elevational view of the arrangement shown in Figure 5; v

Figure '7 is a top plan view of the arrangement shown in Figure 2;

Figure 8 is an elevational view showing a tool bit of small size and nest block therefore;

Figure 9 is a front elevational view of the tool bit and nest block shown in Figure 8;

Figure 10 is a top plan view of a particular form of tool bit, and

0Figure 11 is an end view' of the tool of Figure 1 While I have illustrated a form of my invention as used for supporting form tool bits during grinding operations, it is to be understood that my invention may be used with any instrumentality where it may be found to have utility.

Figure 1 illustrates a form of grindin machine with which the tool holding fixture or unit of my invention is particularly usable. The grinding machine is inclusive of a main frame or pedestal construction IE] upon which is mounted a supplemental frame I within which is journaled a shaft or spindle at the forward extremity of which is mounted a grinding or abrasive wheel I4. The spindle is rotated by means of belts (not shown) contained within a housing l2, the belts being driven by a motor or other suitable source of power contained within the base member Ill. The abrasive wheel I4 is shrouded within a casing l5, a suitable liquid coolant being conveyed to the casing through a tube I6. The coolant, after flowing over the grinding wheel I 4', passes into a flanged table I! and into a pump mechanism (not shown) contained within the base 10 for recirculation.

The frame portion 1 I is formed with an arcuate recess or channel adapted to receive a cresent shaped member 20'. The member 28 is movably supported onthe frame H and is arranged to be moved or adjusted by means of rack and pinion mechanism (not shown) the operating pinion being connected to a manipulating and indexing wheel 22. The indexing wheel 22 is calibrated to accurately locate member 20 in various angular positions with respect to the front face of the grinding wheel. Member 20 is provided with a supporting means for the tool bit retaining fixture of my invention in the form of a ball-like support 23 disposed near the lower end of member 20 while a'straight edge or uniplanar surfaced member 24 is associated with the other end of member 20. A locking means (not shown) for securely positioning member 20 in adjusted position is provided which is adapted to be controlled by manipulation of lever 26.

The present invention is directed to a supporting means usable in con unction with a grinding machine of the character above described for carrying tool bits or the like which are to be: ground or contoured upon a grinding wheel. With particular reference to the structure shownin Figures 2 through 4 inclusive, the tool bit supporting means is inclusiveof a fixture or holder 29 having a body portion provided with a boss portion 30 integrally formed in the lower end thereof. The boss portion 30 is formed with a cylindrical recess adapted to receive a tenon 3| of a fitting or member 32. The fitting 32 isbored and threaded to receive; a bolt 33 adapted to removably secure the fitting or member 32 to the boss 30. The member 32 is formed with a semispherically shaped recess 34 which is adapted to snugly fit and takeover the supporting means or ball 23 formed on the member 23 or other similar construction associated with a suitable grinding machine with which the tool bit holder may be employed.

The upper end of the fixture or holder 29is formed with a laterally extending platform or ledge 36 to which is fitted a hardened plate 3'! secured to the ledge by means of a screw 35, as shown in Figure 4. The plate 3! is formed with an upwardly extending tang 38 for correctly positioning a template 39. The template is formed with a recess adapted to receive the tang 33, a knurled screw 40 being provided to secure the template 39 to the fitting 31; The hardened plate or fitting is accurately located upon the ledge 36 and the template 39 accurately located with respect to the fitting by means of dowels 43. The template 39 is preconfigurated to the form that is desired to be formed on the tool bit and of large size. In the embodiment illustrated, the tel plate contour is twice the size of the contour to be formed on the tool bit. The sizes of the template and tool bit forms are in the ratio of the distance from the center of recess 34 to the plane of the template as compared with the distance from the center of the recess 34 to the upper edge i or ground to predetermined form. The holder is provided with an arcuately shaped boss portion 46, the are or concave surface 4! being generated about the point C in the plane of 'the upper edge of the tool bit blank B.

There is rovided adjacent the boss 45, member 48 having a boss portion 49 provided. with an. arcuate convex surface 5!! arranged to fit the sur face 41. The member 48 is formed with a cvlindrical boss portion 52-, which, is bored to snugly receive a bushing-like member 53 which also extends through an arcuately shaped, o enin formed in the body portion of the holder 29. The m mber 53 is formed at its forward end with a flange 58. the outside diameter of which preferably coincides with the diameter of boss portion 52. As particularlv shown in Figure 5 the peripheral surface of flange 56 is calibrated with suitable indices 51 to indicate degrees of rotary adjustment of member 53. The boss-like portion 52 is provided; with an indexing line 58 for cooperation with the graduations of the flange 56. The other end of the member 53 is provided with a. threaded portion 60, adapted to receive knurled securingnut 6|. The, nut is preferably provided with openings 62,; to accommodate a spanner wrench (not shown) or. other suitable.

tool. Disposed adjacent the nut 6| is a fitting or spacing block 64 having a rear surface which coincides with the inner wall of the nut 5i and its opposite surface 65 of curved or arcuate shape to t the curved surface 68 of the body portion of the holder 29. The knurled nut 6| may be manipulated to secure or look member 48, the block '54- and bushing 53 in adjusted positions and this is accomplished byapplying a suitable tool to the openings 62 and drawing the nut into close engagement to secure the parts together.

The face of portion 49 is provided with graduations 63'; indicating degrees of angularity of the tool blank with respect to a horizontal plane through the upper or cutting edge of the tool. Thus as, shown in Figure 5', the member 69 is canted so as to impart a clearance angle to the face or front edge portion of the tool blank B. The tool blank 13' is also rotated through an angle of 15, degrees as shown in Figures 5 and 6 for the purpose of securing desired clearance angles of a compound nature for the tool.

As shown in Figures 2, 3, and 4, the tool blank B is of a large or standard size which slidably, yet snugly, fits a rectangular opening it in the bushing 53. When using standard large size tool bit blanks, the same may be fixedly held in the bushing by means of set screws H and E2. The cylindrical portion 52 is formed with a radial slot is to provide access to the securing or set screws '52 as illustrated in Figure 2.

The tool bit or blank B mounted in the fixture as shown in Figures 5 and 6 is of a smaller size than the tool bit B. When tools of a smaller size are to be formed or ground, a proper size nest block or fitting i5 is employed. A tool of a small size and a nest block to accommodate same to the dimension of the opening 10 formed in the bushing or holder 53 are shown in Figures 8 and 9. lhe nest block is formed with a recess or channel to snugly accommodate the tool bit 3', while the exterior dimension of block 15 accurately fits the opening 10. The set screws H and i2 engage the nest block '55 in orderto securely hold the tool bit B in the fixture.

The tool supporting fixture of my invention, having the means for universally adjusting the tool bit or blank, provides a medium for imparting varying degrees of angularity or compounding the clearance angles applied to tool bits. Figures 10 and 11 illustrate a form tool having different angularities of clearance on its leading, forward end and trailing edges and illustrates a typical example of tool bit formation that may be configurated or ground utilizing the fixture of my invention. As shown, the leading edge 83 of the tool has a relief or clearance angle of eighteen degrees, the forward end 8! a clearance angle of seven degrees and the trailing edge portion 82 a relief angle of eight degrees. To configurate or grind a tool bit with these specified clearance angles to settings of the grinding ma chine and the tool holder or fixture are as follows:

The grinding machine shown in Figure 1, or any grinding machine having a ball element or other suitable support adapted to accommodate the tool holding fixture, is adjusted so that the ball element or support is moved out of the plane of the grinding Wheel face through an angle computed inthe following manner: In determining the position of the ball support 23 of the grinding machine, a summation of the clearance angles of the leading and trailing edges is first made. Thus a summation of ei ht en, r es an eight grees gives a total. o .twenty six dfigrees,

result so attained is then divided by two, the quotient being thirteen degrees, the angularity that the ball support 23 is to be moved away from the plane of the grinding wheel. In the grinding machine shown, this is accomplished by rotating the knob 22 to move the crescent-shaped member 20 in a clockwise direction as viewed in Figure 1 through rack and pinion mechanism (not shown), the amount of angularity being indicated by graduations (not shown) provided on the periphery of the manipulating knob 22. When the tool bit supporting fixture is disposed upon the ball support 23, the tool bit would normally be tilted at an angle of thirteen degrees." To produce a clearance angle of fifteen degrees upon the forward end portion 8| of the tool, the member 48 is moved through an angle of two degrees indicated by the proper indicia 61 registering with the index line 68. This operation adds two degrees to the thirteen degrees so as to provide the fifteen degree clearance angle upon the end of the tool bit.

To provide the clearance angle on the leading end of eighteen degrees and a clearance of eight degrees on the trailing edge, it is then necessary to rotate or roll the bushing 53, carrying tool bit or tool blank through an angle of five degrees viz. until the five degree graduation 57 registers with the index line 58 formed on the cylindrical portion 52 of member 48. This operation adds five degrees to the initial cant or angle of thirteen degrees made on the ball support 23, and the resulting summation of eighteen degrees is the clearance angle sought for the leading edge of the tool. The five degrees of cant is, in effect, subtracted from the thirteen degree setting of the support 23 resulting in eight degrees, the desired clearance angle for the trailing edge 82 0f the tool bit.

By this means of computation and adjustment of the supporting member 23 of the grinding machine, the angular adjustment of member 48 and the radial position of the tool bit supportin bushing 53, many combinations of clearance angles for a tool bit may be obtained. The relative positions of member 48 and bushing 53 with respect to the body 29 of the tool supporting fixture may be locked in adjusted position by drawing up the knurled nut 6|. After these adjustments for various angles of clearance have been effected, the operator places the fixture in operative association with the grinding machine by fitting the socket 34 of the fixture over the support 23, to facilitate the bringing of the tool bit blank into engagement with the face of the grinding wheel I4 as shown in Figure 1. The operator then rocks the tool holding fixture on the ball support 23 while keeping the template configuration in the zone of the straight edge to bring various points and portions of the tool bit into engagement with the grinding wheel to finally shape the tool bit in correspondence with the configuration of the template. During the grinding operation, the abrasion of the tool blank continues until the pattern portions of the template engage the straight edge, thus preventing any further abrasion or grinding of tool, the finished tool form then bearing the pattern predetermined by the template. In the embodiment illustrated, the distance from the center of the ball support 23 to the template is twice the distance from the center of the ball support to the upper or cutting edge of the tool blank, a tool bit form or configuration of a high degree of accuracy is obtained due to the fact that the template or pattern from which the tool is configurated is of greater size than the finished tool bit form. While I have found this proportion of template size to tool bit size to be satisfactory, it is to be understood other proportions of template size to tool bit size may be employed without departing from the spirit and scope of the invention.

It is apparent that, within the scope of the invention, modifications and different arrangements may be made other than is herein disclosed, and the present disclosure is illustrative merely, the invention comprehending all variations thereof.

What I claim is:

A holder by which a tool may be supported and manipulated in cooperating relation with respect to the rotary abrading wheel of a grinding machine having a holder support in the form of a ball below said wheel and a template guiding surface above said wheel, said holder being in the form of an arm and the lower end thereof having a spherical socket for accommodating said ball to permit limited universal movement of the lower end of said holder upon said ball in planes at right angles with respect to one another, the upper end of said holder being formed to provide a transversely extending seat for a tem-- plate which is adapted to cooperate with said guiding surface, an intermediate portion of said holder being arcuate and the walls thereof providing concave and convex seats, said intermediate portion being formed with a slot which extends through said seats, a sleeve extending through said slot and having a bore in which said tool is adapted to be removably secured, cooperating elements located at the opposite sides of said holder and engaging said seats, said elements having surfaces which conform to said seats and being apertured to accommodate opposite ends of said sleeve, said elements being adjustable on said seats to vary the angle of inclination of said tool and said sleeve being rotatable in said elements to adjust said tool about its longitudinal axis, and means for locking said elements and sleeve in the positions to which they are adiusted.

EDD C. OLIVER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 467,857 Conradson Jan. 26, 1892 565,644 Taylor Aug. 11, 1896 704,348 Lapointe July 8, 1902 748,651 Reimann Jan. 5, 1904 765,304 Bishop July 19, 1904 1,058,358 Cookingham Apr. 8, 1913 1,121,995 Elvers Dec. 22, 1914 1,255,962 Warner Feb. 12, 1918 1,431,024 Munthe Oct. 3, 1922 1,771,621 Fowler July 29, 1930 1,987,832 Knight Jan. 15, 1935 2,144,095 Zwick Jan. 17, 1939 2,179,869 Swanson Nov. 14, 1939 2,375,620 Bura May 8, 1945 2,381,034 Bura Aug. 7, 1945 2,475,796 Mader July 12, 1949

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